Strain control and electrical properties of stripe-patterned Si/Si _1-xGe_x/Si(1 0 0) heterostructures

In a Si/Si_1-xGe_x/Si(1 0 0) heterostructure patterned into a shape striped in the 〈1 1 0〉 direction, strain control of capping Si and Si_1-xGe_x layers is investigated. The Raman scattering analysis of the stripe-patterned Si/Si _1-xGe_x/Si(1 0 0) heterostructure indicates strain relaxation in the Si_1-xGe_x layer and introduction of tensile strain into the capping Si layer by submicron stripe patterning. It is found that the degree of strain relaxation in the Si _1-xGe_x layer is strongly dependent on the stripe width, the capping Si layer thickness and the Si_{1- x}Ge_x layer thickness. Four-terminal resistivity measurement of the strain-controlled Si/Si_1-xGe _x/Si(1 0 0) heterostructure shows an increase of the electron and hole conductivity for the tensile strained capping Si layer and a decrease of the hole conductivity for the partially relaxed Si_{1- x}Ge_x layer.